<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>买点书</title>
</head>

<style>
  .book{
    display: flex;
    padding-left: 20px;
  }

  .book p{
    margin-right: 80px;
  }
</style>

<body>
    <div id="app">
        <div>
            <p>请选择你要购买的书籍</p>
            <ul v-for="item in arr">
                {{item.name}} <button @click="bug(item.name)">买书</button>
            </ul>
            <table border="1" width="500" cellspacing="0">
                <tr>
                    <th>序号</th>
                    <th>书名</th>
                    <th>单价</th>
                    <th>数量</th>
                    <th>合计</th>
                </tr>
                <tr v-for="(item,index) in arr">
                    <td>{{index +1}}</td>
                    <td>{{item.name}}</td>
                    <td>{{item.price}}</td>
                    <td>{{item.count}}</td>
                    <td>{{item.price * item.count}}</td>
                </tr>
            </table>
           
            <p>总价格为:{{arr.reduce((sum,item)=> sum += item.price * item.count,0)}} </p>
        </div>
    </div>
    <script src="./vue.js"></script>
    <script>
        const app = new Vue({
            el: '#app',
            data: {
                arr: [
                    {
                        name: "水浒传",
                        price: 107,
                        count: 0,
                    },
                    {
                        name: "西游记",
                        price: 192,
                        count: 0,
                    },
                    {
                        name: "三国演义",
                        price: 219,
                        count: 0,
                    },
                    {
                        name: "红楼梦",
                        price: 178,
                        count: 0,
                    },
                ],
 
            },
            methods: {
                bug(name) {
                    const index = this.arr.findIndex(item => item.name === name);
                    this.arr[index]['count']++
                }
            }
        })
    </script>
</body>

</html>